Torrential downpours are possible, with as much as 30mm of rainfall in one hour and 60mm in three hours, while large hail, frequent lightning and strong, gusty winds will be additional hazards, forecasters warned.

The hot weather and very high afternoon temperatures have led to an amber warning for thunderstorms valid from 2pm to 8pm in the East Midlands and east of England.

Torrential downpours are possible, with as much as 30mm of rainfall in one hour and 60mm in three hours, while large hail, frequent lightning and strong, gusty winds will be additional hazards, forecasters warned.

Those in the areas covered by the warnings can expect flooding of homes and businesses, which could happen quickly, with damage to some buildings from floodwater.

Was lashing down here before, overflowing the gutters. Our Greek style former lawn now has some blades of grass coming through. I'm well known for hating rain as a result of four years in Bangor as a student, but not complaining now. At least we're high enough here not to get flooding but I guess others may well not be so lucky.

Warm weather brings freshwater jellyfish to Shropshire canalFirst UK sighting of tiny jellyfish species normally found in the Yangtze basin in China

First came the wasps, exotic sharks and marauding seagulls. Now the long hot summer has revealed another initially alarm-inducing animal in British waters – or more precisely, in the Middlewich branch of the Shropshire Union Canal.

Freshwater jellyfish more normally found in the Yangtze basin in China have been spotted swimming in the waters near Bridge 23 of the canal between Middlewich and Winsford, according to the Canal & River Trust.

The jellyfish, Craspedacusta sowerbii, is transparent, the size of a 10p coin, and completely harmless to humans. It has never been recorded before in the charity’s 2,000 miles of canals and rivers.

Storm Callum expected to bring more heavy rain and flooding to UKPeople in western parts of UK warned to expect more heavy rain and strong winds

Heavy downpours are expected on Saturday as Storm Callum continues to batter the UK and cause disruption, with flights and train services cancelled.

The Environment Agency has issued flood warnings for parts of the Dorset coast, as well as 58 flood alerts across England, while Natural Resources Wales has 28 flood warnings and 39 flood alerts in place.

UK weather forecast: Temperatures set to plunge below zero as warmth gives way to frosty mornings

Frost and freezing temperatures are expected to hit parts of the UK as a spell of colder weather begins to take hold this week.

Northern parts of Britain are likely to see some crisp mornings as autumn starts to set in, while the mercury could drop below zero on Tuesday night into Wednesday in the Scottish Highlands.

It comes after Storm Callum pummelled the country over the weekend, causing severe flooding in Wales and leaving at least three people dead.

At the same time, southern parts of England enjoyed unseasonably warm conditions, which look set to continue in the south east on Tuesday, where some places could see highs of 23C - before potentially falling into single figures at the weekend.

Despite some reports to the contrary, the Met Office said it did not expect snow to fall in the UK during October.